NAME

su  −  substitute user id temporarily

SYNOPSIS

su [ userid ]

DESCRIPTION

Su demands the password of the specified userid, and if it is given, changes to that userid and invokes the Shell sh(1) without changing the current directory or the user environment (see environ(5)). The new user ID stays in force until the Shell exits.

If no userid is specified, ‘root’ is assumed.  To remind the super-user of his responsibilities, the Shell substitutes ‘#’ for its usual prompt. 

SEE ALSO

sh(1)

7th Edition